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We now need to look at physical evidence on the occupant. That physical evidence is in the form of abrasions which were described in the autopsy report with the first abrasion being one which is across the left hip in a lap belt distribution.

I would get abrasions like that when we would ride crash tests from collisions. You'd typically see an abrasion like that on this hip and you'd see an abrasion like that on the other hip.

That's not what we see in the Earnhardt accident, because instead, we see an abrasion that is a longer abrasion, a little over eight and a half inches long, preceding in a diagonal fashion basically paralleling the inguinal ligament.

This is further evidence that just like the physical evidence on the belt tells us that the separation occurred under load, because after the separation occurs, if the occupant continues to move forward, he now has a different kind of restraint system that has no left lap belt but it still has a crotch strap and it still has a right lap belt and it still has shoulder harnesses.

And as you go into that system, as you move forward and to the right in this case, it leaves a diagonal abrasion consistent with the crotch strap forming a loop with the right lap belt.

Those marks tell us that Dale Earnhardt moved forward into a separated belt which could not have occurred unless the belt separated under load.

So the physical evidence is clear, both on the belt and in the injuries, that the belt separated under load. We've addressed these two.

Other parts of the report which you will receive will talk about fiber analysis showing that these were torn fibers, not fibers cut with an instrument. DNA analysis that says that the blood on the belt is the same as the blood in the car.

There was a difference in the way it was deposited. If the blood was deposited first and you cut across it, you would expect to see similar blood deposits on both sides of the cut.

What we see is different kinds of blood deposits on one side than you see on the other side, different amounts and ways in which that blood is deposited.

You've seen the medical examiner photographs and there were extensive interviews of those that had access to the belt. The conclusion is clear: There was no cutting of the belt afterwards. It's a belt that separated under load.

We'll now go into the injury causation analysis. And to begin with, we'll look at vehicle dynamics. As I mentioned, it's the province of the reconstruction.

Jim Hunter will introduce the reconstruction team so you can hear the presentation from then and then I'll come back and fill in the rest of this analysis.

JIM HUNTER: Thank you. Dr. Dean L. Sicking is a civil engineering professor at the University of Nebraska at Lincoln. He is one of the world's leading independent researchers on barrier and crash safety. His work includes the study and analysis of vehicle crashes.

Many of Dr. Sicking's recent contributions have come through his work at the Midwest Roadside Safety Facility in Lincoln. Dr. Sicking and his Nebraska team have been responsible for many patented highway safety features. Some of their developments include energy-absorbing guard rails, crash cushions and median barriers.

As part of its broader mission, Dr. Sicking's Midwest center also conducts full scale crash testing and structural testing of vehicles and safety devices. One project involves the center's ongoing work with the Indy Racing League and NASCAR on energy absorption barrier systems.

Other projects involve vehicle crash modelling and accident reconstruction, as well as computer simulation of vehicle dynamics. Dr. Sicking is personally responsible for 16 separate roadside safety patents in the United States. His designs have also been adopted in numerous foreign countries.

Dr. Sicking is an influential member of many national safety committees. He earned BS, MS and Ph.D. degrees at Texas A & M University. It's my pleasure to welcome Dr. Dean Sicking.

DR. DEAN L. SICKING: Thank you, Jim. Today I would like to summarize the work that was done at the University of Nebraska and the Midwest Roadside Safety Facility. That work was led by myself and Dr. John Reid, who is an associate professor in mechanical engineering at the University of Nebraska.

First thing I want to do is review the crash that occurred on the last lap in the fourth turn of the Daytona 500 of this year. If you'll recall, the No. 3 car lost control toward the inside of the track, the driver immediately corrected, regained the track where he was struck, where there was a collision between the No. 36 and No. 3 car.

Thereafter, the No. 3 car slammed into the barrier.

Our job was to obtain the vehicle kinematics throughout this event. By vehicle kinematics, I mean the motions of all the vehicles throughout the crash.

Of primary interest to us was the barrier impact conditions. What was the speed, angle and orientation of the No. 3 car when it struck the barrier? And the same thing for the No. 36 car.

We also were very interested in the collision between the No. 3 and No. 36 cars, and we also needed to know what the barrier impulse imparted to the No. 3 car was. By barrier impulse, I mean the forces applied to the No. 3 car during the barrier impact.

This is important for determining or estimating the injury causation that Dr. Raddin will talk about in a minute.

Any accident reconstruction begins with collection of all available evidence. This accident, there was a great deal of evidence. At the site, there was a significant amount of tire marks and barrier marks available. There was also -- the vehicle was available for crush measurements.

Each vehicle in the race carried a GPS receiver which recorded -- which was used to record the position of the vehicle five times every second, which, again, another important source of information. And, finally, this crash event was actually captured on seven video cameras, which could be used to locate each of the vehicles throughout the event.

Once we've collected all available data and analyzed it, we were able to estimate vehicle conditions and impact scenarios throughout the event. We wanted to then verify critical impact conditions for this case, that would be the No. 3 car impact with the barrier.

To do that verification, we conducted a full scale crash test to make sure that the energy of impact that we've estimated for this crash was correct.

Finally, we did a detailed computer model of the full crash event. The only way we could reconstruct the full crash event was with computer modelling.

Because, as you saw in this crash, this vehicle was in a non-tracking mode, meaning that the rear tires were not following the front tires when it struck the barrier. Under today's technology, it is not possible to conduct a full scale crash test in a non-tracking mode at speeds up to 160 miles per hour.

So the only way to fully reconstruct this event was to reproduce a computer model which we'll talk about later.

I want to give you a couple definitions. Barrier impact is controlled by the amount of energy that has to be dissipated during the impact and the direction of the forces applied to the vehicle.

There's two parameters associated with the velocity vector. That's the speed and the direction. The speed of a vehicle, I think everyone in here can appreciate that the faster a car is traveling, the more energy has to be dissipated during the barrier impact and the more severe the event.

The other thing associated with the velocity vector is its angle relative to the barrier. We call that the trajectory angle. The trajectory angle also has a great influence on the amount of energy that has to be dissipated during a vehicle collision with the barrier. So we'll be talking about speed and trajectory angle, and those control how much energy must be dissipated. The third parameter is heading angle. That's the orientation of the vehicle relative to the barrier at the time of impact.

Heading angle controls the point at which forces are applied to the vehicle and the direction they're applied to the vehicle, which, in turn, affects how forces are applied to the occupant's seat and to the driver restraint system. Which, again, becomes an important part of the injury causation.

When we went to the track, we found a great deal of tire mark evidence. We actually found marks associated with all eight tires -- well, seven tires and one suspension -- recall that the right rear wheel of the No. 3 car was broken off during its collision with the No. 36 car.

But there were scrape marks associated with the right rear shock absorber and a u-bolt on that suspension and these are those scrape marks and clearly identified during this crash.

What we found was, when we analyzed the angles of these tire marks when they approached the barrier, was that the front tires for both cars had a significantly higher angle of incidence with the barrier than did the rear tires.

This indicates that just as shown in the video, these vehicles were rotating into the barrier at the time they struck the wall.

That when a vehicle is rotating into the barrier, the front wheels are carried closer to the barrier while the rear wheels are carried further away from the barrier.

That would make the angle of approach for the front tires to be higher than the actual trajectory angle, and the angle of approach for the rear tires to be lower than the actual trajectory angle. From tire evidence alone, we were able to conclude the trajectory angle for the No. 3 car was between 12 and 15 degrees and the trajectory angle for the No. 36 car was between 10 and 12 degrees.

There's been speculation both the 36 and 3 car were traveling at the same speed and therefore they had the same severity of impact with the barrier.

What this tire mark evidence clearly indicates is that the severity of the No. 3 car impact with the barrier was significantly different, just a two or three-degree change in trajectory angle creates a 25-percent increase in the energy that must be dissipated during the barrier impact. That's quite a substantial difference.

The GPS data that each car carried a receiver that allowed Sport Vision to record its location five times every second. From that data we were able to identify the location of this receiver throughout the event by taking the differences in location between each recording event where it will determine both the velocity and the trajectory angle of that vehicle.

However, because there was only one receiver on the vehicle, we were not able to get heading angle. So from the GPS data we were able to get velocity, in terms of speed and trajectory angle, but not heading angle.

We were primarily concerned, again, with the barrier impact and the collision between the No. 3, No. 36 car.

What we found from the GPS data was that the speed of the vehicles at time of collision with the barrier was between 156 and 161 miles per hour. And that the trajectory angle data from the GPS exactly matched the data from the tire marks. It's always good when all the evidence gives you the same answer.

The collision between the No. 3 and No. 36 car, remember, we found that this collision didn't change the speeds of the vehicles greatly, but it did change the direction. So it's the total velocity change, including the change in direction of the speed, amounted to about nine to eleven miles per hour for this impact event.

Now we go to the photogrammetric. The seven video cameras that captured the event take frames approximately 30 times every second. Each frame can be used through photogrammetric to determine the location of the vehicles.

The way that works is that we first produce a computer-aided drawing, detailed drawing of all the background features of the track. Produce a drawing from a camera view from (inaudible) that produce a camera from that drawing package that exactly replicates the photograph.

When we've completely replicated all the background information as well as the car location, we believe we've reconstructed the location of car during that point in time.

By reviewing or working with all seven of the video camera views, we were able to determine a great deal of information about this accident. What we found was -- this still was taken from a video camera just at the point where the No. 3 car is coming back on to the track.

At this point the driver has regained, or has attempted to regain control, steered the car back on to the track, and now has a velocity here of about 164 miles per hour. His trajectory angle relative to the barrier is along this path and has an angle relative to the barrier of over 17 degrees.

The rest of this group of cars is traveling at about 170 miles per hour. Even though he's a little bit ahead of them, they're gaining fast.

And from this point, this point in the accident to the next frame here, is about 300 milliseconds, a little less than 300 milliseconds or a little less than three-tenths of a second. Meaning there was really no time for the No. 36 car driver to respond and take any evasive action to avoid this collision.

The GPS data showed again at this point, the photogrammetric showed at this point this vehicle was traveling at about 162 miles per hour, and the No. 36 car was still traveling in the neighborhood of 170 miles per hour, 169, 170, along with the rest of this pack of cars here. This vehicle had an orientation of heading angle of about 26 and a half degrees, that heading angle was beginning to diminish. It was beginning to be straightened out back toward the track at this point.

Its velocity vector into the barrier was still about 17 degrees. The collision between the 36 car and the 3 car did two things. First thing it did was it slowed down the velocity of the car, of the No. 3 car, toward the barrier. Slowing that velocity down is a good thing; it reduced its effective angle, trajectory angle, relative to the barrier from about 17 degrees to about 13 or 14 degrees.

The other thing it did is it caused the No. 3 car to start to rotate clockwise into the barrier, which significantly changed its heading angle.

What we see here is a frame from just before impact. You can clearly see the heading angle into this barrier is much larger than it was in the previous view, and that controlled how the forces were delivered to the No. 3 car; meaning that it was more of a frontal hit than a side hit.

Estimated impact conditions from the photogrammetric analysis closely replicated the previous results from the GPS data that we gave a little bit closer estimate of speed, 157 to 160 miles per hour. Heading angle is a little tighter, tolerance on trajectory angle. This is our first estimate of heading angle that we were able to determine from both of these cars.

Again, the trajectory angle for the 3 car and 36 were quite different, meaning a significantly more severe hit for the No. 3 car.

We also, again, found from the photogrammetry that the total velocity change during the collision between the No. 3 and No. 36 car was between nine and eleven miles per hour; that the barrier impact occurred about four-tenths of a second after the collision with the No. 36 car and that the total velocity change during the impact for the No. 3 car was between 42 and 44 miles per hour.

Large majority of all off-road collisions that result in fatality occur at speeds well below that number. This is a severe hit.

We wanted to verify those estimated impact conditions, so we conducted a full scale crash test to try to reproduce the damage between the -- of the No. 3 car by running a controlled crash test at roughly the same energy conditions that we estimated from the previous slide.

Our goal, again, was to replicate vehicle damage. We started at the rear and compared damage from the rear axle forward and found both a similar pattern and a similar magnitude of damage for both vehicles indicating that our original estimate of the energy of this impact was very close.

We then went on to full scale computer modelling. We wanted to determine, conduct a full reconstruction of this accident and determine what happened during the barrier impact as best we could. So we developed a finite element model using state of the art software in conjunction with Altair Incorporated. What you see up here on the right is a structural frame of a Winston Cup car.

In fact, Dale Earnhardt's car. And down here is that same structural frame with all of the ancillary components including the engine, transmission, radiator, etc. the first question we had was is this model accurate.

So we replicated the full scale crash test using our computer model. In this case, we again compared damage predicted by the computer simulation to the actual damage to the No. 3 car. We also compared the timing of the accident of the crash. In other words, at what time did the radiator strike the wall?

At what time did the wheels strike the wall and the engine, etc.? We also compared the overall impulses applied to the two vehicles and the nature of those impulses, and they compared very well.

So we were very satisfied that this was a validated model and could be used to reconstruct the Earnhardt crash.

Again, the vehicle damage was quite similar, as you see here. And this wasn't just the overall damage. We were looking at damage to individual components, including the headers and the roll cage. The next thing we did was conduct a simulation of the full scale crash, of the actual crash.

This vehicle was impacting the barrier at the 158 mile per hour estimate we had for impact speed with a 13.6 degree angle of incidence to the barrier with a heading angle of about 57 degrees.

What this simulation showed us was that this vehicle, even without the No. 36 car here to influence it, didn't redirect. It wasn't steered away from the barrier. During a typical barrier impact, the front of the car would be pushed outward and the rear would come around and have a rear-end slap. That would be a typical redirection hit. That's what we would call that.

Another alternative, if they have a high angle relative to the barrier high heading angle, sometimes the vehicles will spin out and the right side will spin around and slap the barrier.

In either event, you have two impact events that take out a lot of velocity. In this situation, the vehicle ran into the barrier and kept the same heading angle. It was really no redirected force applied, no moments applied that changed the angle of the vehicle indicating that this was a critical angle hit. All of the velocity, lateral velocity, had to be taken out during the primary impact, which is a worst-case scenario.

Again, the vehicle damage predicted by our model compared very well with that observed on the No. 3 car throughout the vehicle, not just the overall that I showed here today.

In summary, we believe we very accurately estimated the actual impact conditions of the No. 3 car. 157 to 160 miles per hour; 13 to 14-degree trajectory angle; 55 to 59 degree heading angle; and an overall crash duration of about 800ths of a second. Total velocity change during the event between 42 and 44 miles per hour.

The velocity change of the No. 3 car when it collided with the 36 car was in the nine to eleven mile per hour range. The crash test and the computer modelling accurately reproduced damage to the No. 3 car. And, finally, I want to step back and look at what we've done for going forward.

(go to www.maxpages.com/earnhardtisno1/Earnhardt_Report_Trnscpt_Part3 for Part 3 of the transcript)

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